81
current meter
physical and chemical requirements such as tank size, temperature, light,
substrate, food supply, and prevention of diseases and contamination.
Cumacea (cumaceans) order of class Malacostraca, subphylum Crustacea (phylum
Arthropoda). Small (up to a few em), mainly marine crustaceans that live
buried in sand and mud bottoms, with the head sticking out of the sediment. Thorax (~Crustacea) and head are greatly enlarged and the abdomen
is long and slender, which together gives the cumaceans its typically
comma-shaped form. They feed by filtering particles from the water, or
directly from the bottom. Cumaceans are periodically pelagic; swarming is
related with reproduction and molting .
.. . -
... .. .
Cumacea. (Barnes 1987)
..... ,', "
.' .. ""_II,...
: .... \i.. •.
.. "
.... "
_101" ...
curie unit of radioactivity (1 Ci=3.7 10 10 disintegrations per second) equivalent
to the radiation by 1 g of radium, the approximate quantity of radium isolated by Madame M. Curie (1867-1934) in her professional lifetime. The
curie has been replaced by the becquerel.
current meter instrument to measure speed and direction of water currents.
Different types of current meters have been used in oceanography. Before the
introduction of automatic self-recording instruments, measurements were
mainly made from ships, with often interference of ship's movements.
Modern instruments are anchored on a line with subsurface floats, which
makes the possibility of surface movements interfering with the measurements much smaller. They record the current data on tape, and can remain
on station for many months. Recovering of deeply moored instruments is
often by acoustic releases. The current sensor is usually mechanical (impellor or
rotor) and the number of revolutions per unit time is proportional to the cur-
current meter
physical and chemical requirements such as tank size, temperature, light,
substrate, food supply, and prevention of diseases and contamination.
Cumacea (cumaceans) order of class Malacostraca, subphylum Crustacea (phylum
Arthropoda). Small (up to a few em), mainly marine crustaceans that live
buried in sand and mud bottoms, with the head sticking out of the sediment. Thorax (~Crustacea) and head are greatly enlarged and the abdomen
is long and slender, which together gives the cumaceans its typically
comma-shaped form. They feed by filtering particles from the water, or
directly from the bottom. Cumaceans are periodically pelagic; swarming is
related with reproduction and molting .
.. . -
... .. .
Cumacea. (Barnes 1987)
..... ,', "
.' .. ""_II,...
: .... \i.. •.
.. "
.... "
_101" ...
curie unit of radioactivity (1 Ci=3.7 10 10 disintegrations per second) equivalent
to the radiation by 1 g of radium, the approximate quantity of radium isolated by Madame M. Curie (1867-1934) in her professional lifetime. The
curie has been replaced by the becquerel.
current meter instrument to measure speed and direction of water currents.
Different types of current meters have been used in oceanography. Before the
introduction of automatic self-recording instruments, measurements were
mainly made from ships, with often interference of ship's movements.
Modern instruments are anchored on a line with subsurface floats, which
makes the possibility of surface movements interfering with the measurements much smaller. They record the current data on tape, and can remain
on station for many months. Recovering of deeply moored instruments is
often by acoustic releases. The current sensor is usually mechanical (impellor or
rotor) and the number of revolutions per unit time is proportional to the cur-